The Molecular Mechanisms Study of Engeletin Suppresses RANKL-Induced Osteoclastogenesis and Inhibits Ovariectomized Murine Model Bone Loss

Mingzhe Feng; Lin Liu; Jiang Wang; Jialang Zhang; Zechao Qu; Yanjun Wang; Baorong He

doi:10.2147/JIR.S401519

The Molecular Mechanisms Study of Engeletin Suppresses RANKL-Induced Osteoclastogenesis and Inhibits Ovariectomized Murine Model Bone Loss

J Inflamm Res. 2023 May 24:16:2255-2270. doi: 10.2147/JIR.S401519. eCollection 2023.

Authors

Mingzhe Feng^#¹, Lin Liu^#², Jiang Wang¹, Jialang Zhang¹, Zechao Qu¹, Yanjun Wang³, Baorong He¹

Affiliations

¹ Department of Spine Surgery, Honghui Hospital, School of Medicine, Xi'an Jiao Tong University, Xi'an, People's Republic of China.
² Department of Critical Care Medicine, Honghui Hospital, School of Medicine, Xi'an Jiao Tong University, Xi'an, People's Republic of China.
³ Department of Emergency, Honghui Hospital, School of Medicine, Xi'an Jiao Tong University, Xi'an, People's Republic of China.

^# Contributed equally.

Abstract

Objective: Osteoclastogenesis, the process of osteoclast differentiation, plays a critical role in bone homeostasis. Overexpression of osteoclastogenesis can lead to pathological conditions, such as osteoporosis and osteolysis. This study aims to investigate the role of Engelitin in the process of RAW264.7 cell differentiation into osteoclasts induced by RANKL, as well as in a mouse model of bone loss following ovariectomy.

Methods: We used RANKL-stimulated RAW264.7 cells as an in vitro osteoclast differentiation model. The effects of Eng on morphological changes during osteoclast differentiation were evaluated using TRAP and F-actin staining. The effects of Eng on the molecular level of osteoclast differentiation were evaluated using Western blot and q-PCR. The level of reactive oxygen species was evaluated using the DCFH-DA staining method. We then used ovariectomized mice as a bone loss animal model. The effects of Eng on changes in bone loss in vivo were evaluated using micro-CT and histological analysis staining.

Results: In the in vitro experiments, Eng exhibited dose-dependent inhibition of osteoclast formation and F-actin formation. At the molecular level, Eng dose-dependently suppressed the expression of specific RNAs (NFATc1, c-Fos, TRAP, Cathepsin K, MMP-9) involved in osteoclast differentiation, and inhibited the phosphorylation of proteins such as IκBα, P65, ERK, JNK, and P38. Additionally, Eng dose-dependently suppressed ROS levels and promoted the expression of antioxidant enzymes such as Nrf2, HO-1, and NQO1. In the in vivo experiments, Eng improved bone loss in ovariectomized mice.

Conclusion: Our study found that Eng inhibited RANKL-induced osteoclast differentiation through multiple signaling pathways, including MAPKs, NF-κB, and ROS aggregation. Furthermore, Eng improved bone loss in ovariectomized mice.

Keywords: MAPKs; RANKL; ROS; engeletin; osteoclastogenesis.

Grants and funding

This study was supported by a grant from Key project of National Science Foundation of China (82070909) and Key project of Natural Science Basic Research Plan of Shaanxi Province(2022JZ-43).